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pathfinder
19-03-2005, 10:16 PM
Hello Gentlemen,
OK, I got a bit of confidence from your posts, so I decided to take a look at this thermostat.
By the way, the model is a Blomberg 6248.
I bought it secondhand about 5 years ago, and I believe it is a "Comet" special, meaning that it could have been manufactured anywhere....
And if it's anything like Comet's "own brand" TV's, then getting a circuit diagram or parts is just a joke IMO.

Anyway, the first part of the job was a total bugger...that is removing the front cowling, or cosmetic cover.
As with all Domestic White Goods stuff I've encountered, everthing is built around the "Finished Look" as the fashion designer saw it, with all the actual "real" workings just stuffed in just as an afterthought.
By now, the plastic had gone brittle, so the "flexi catches" didn't flex, but preferred to just snap.

I got the front panel off anyway and after streching and untangling a mess of stuffed in cabling, finally had a look at the Fridge thermostat.

Phew, it looked a bit of a daunting task feeding that sensor wire down to wherever it went and I began to lose heart.
Then I noticed that the thermostat itself was of an "open" construction...with the switching elements visible.
I couldn't believe it...nearly all switches are sealed these days.
Leaving switches to pass high current in air is just asking for trouble eventually IMO.

By now the unit had been switched off for three-quarters of an hour, so I guessed it would be best to retrace my steps and put it back together again, before stuff started to thaw.

But before I did, I reckoned on giving the open switching a couple of blasts of switch cleaner first.
Couldn't do any harm, and could possibly do some good.

So I put everything back together again and switched on.

The whole thing sprang to life, like a drowning man surfacing for the first time and gasping for air.
Both compressors well working full out and the fans were humming.
So I made a cup of tea and turned up the radio...

About a half hour later I heard the fans turn off.

Absolute silence on the Radio.

Now, I'm a firm believer in Murphy, so I took it with a pinch of salt...

Well, it's been nine hours now and not a glitch on either the TV or Radio.

I can't impress upon you enough as to how bad this RFI was.
It would completely obliterate TV, including Digital TV, Radio and Audio and I'm sure it must have been affecting half the folk in the street.
I've had less inteference from somebody using an Electric Welder.

Now I'm not saying that Switch Cleaner is the best solution, but with the prospect of changing out that thermostat, I think I'll be thankful for the moment!

As a final point, when I was struggling to take off the cover, I happened to break a little bit of plastic off the corner.
Now the Wife is giving me Gyp...

I should have known already though...it's impossible to win!


Anyway Gent's...thanks for your help...and I'll be back for some advice on how to change out that stat when it eventually does go belly up!

cheers

PF

Brian_UK
20-03-2005, 11:31 PM
Good news Pathfinder, well done and glad to hear that your first problem is resolved.

Yes, most of those front covers are designed as a once only fit, the norm is to fit a screww behind a glued plastic plug - you don't know it's there until after the plastic cracks !!